Int J Clin Exp Pathol 2015;8(5):5812-5820 www.ijcep.com /ISSN:1936-2625/IJCEP0007951 Case Report Therapy-related acute myeloid leukemia with eosinophilia, basophilia, t(4;14)(q12;q24) and PDGFRA rearrangement: a case report and review of the literature Jun Zhou1, Peter Papenhausen2, Haipeng Shao1 1Department of Hematopathology and Laboratory Medicine, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL, USA; 2Cytogenetics Laboratory, Laboratory Corporation of America, Research Triangle Park, NC, USA Received March 13, 2015; Accepted April 26, 2015; Epub May 1, 2015; Published May 15, 2015 Abstract: The myeloid and lymphoid neoplasms with eosinophilia and PDGFRA gene rearrangements usually show a good response to Imatinib and are typically associated with a normal karyotype, occasionally exhibiting a second- ary chromosomal abnormality associated with clonal evolution. Five variant translocations involving PDGFRA have been reported. Here, we report a rare case of therapy-related acute myeloid leukemia with PDGFRA rearrangement after chemotherapy for prior B lymphoblastic leukemia (B-ALL). The patient had a history of BCR-ABL negative, hy- podiploid B-ALL in complete remission after chemotherapy. However, 15 months later the patient developed acute myeloid leukemia with rapidly increasing eosinophilia, basophilia and a complex karyotype that included a novel t(4;14)(q12;q24). FIP1L1 was not associated with the PDGFRA rearrangement. The patient had a very aggressive clinical course, and died from the disease shortly after diagnosis. This is the first case of a primary therapy-related myeloid neoplasm with secondary PDGFRA rearrangement. The t(4:14)(q12;q24) is joining the growing list of the variant translocations involving PDGFRA. Keywords: Acute myeloid leukemia (AML), PDGFRA, eosinophilia, basophilia, therapy-related myeloid neoplasm Introduction slocations with PDGFRA gene identified so far: t(2;4)(p22;q12) [4], ins(9;4)(q33;q12q25) [5], Myeloproliferative and lymphoid neoplasms t(4;10)(q12;p11) [6], t(4;12)(q12;p13) [4, 7] and associated with rearrangement of PDGFRA is t(4;22)(q12;q11.2) [8]. The FIP1L1-PDGFRA and a newly recognized entity in the 2008 World other variant translocations of PDGFRA result in Health Organization (WHO) classification of a constitutively activated tyrosine kinase that tumors of hematopoietic and lymphoid tissues, transforms hematopoietic cells, and therefore it and most commonly manifest as de novo chro- is a therapeutic target for tyrosine kinase inhibi- nic eosinophilic leukemia, but also less fre- tors [9]. The small molecule tyrosine kinase quently as acute myeloid leukemia or inhibitors from the 2-phenylaminopyrimidine T-lymphoblastic leukemia [1]. The most com- class of compounds, e.g. Imatinib mesylate mon PDGFRA rearrangement is FIP1L1-PDGFRA (Gleevec), have been shown to be effective in fusion, which results from an approximate 800 the treatment of neoplasms associated with kb interstitial chromosomal deletion that inclu- PDGFRA rearrangement [4, 7, 10-12]. des the cysteine-rich hydrophobic domain 2 (CHIC2) locus at 4q12 [2, 3]. These cases typi- The myeloid neoplasm with FIP1L1-PDGFRA cally show a normal karyotype by conventional translocation often show atypical mast cell pro- cytogenetic study, and the FIP1L1-PDGFRA liferation in the marrow. The mast cells are fusion is inferred by fluoroscent in situ hybridi- usualy spindle-shaped with aberrant expres- zation (FISH) study for CHIC2 deletion. There sion of CD25. But clusters of mast cells cha- are five non-FIP1LI associated balanced tran- racteristic of systemic mastocytosis are absent Therapy-related AML with rearranged PDGFRA Figure 1. B-lymphoblastic leukemia at initial diagnosis. A. Predominance of large lymphoblasts with round to in- dented nuclei, fine chromatin, and basophilic cytoplasm with cytoplasmic vacuoles (Aspirate smears, Wright stain, 1000 ×). B. Hypercellular marrow with sheets of blasts (Bone marrow core biopsy, H & E stain, 100 ×). Figure 2. Restaging bone marrow biopsy after chemotherapy for B-ALL showed multilineage dysplasia and focal eo- sinophilia. A. Megakaryocytic dysplasia with hypolobulated nuclei (Aspirate smears, Wright stain, 100×); B. Erythroid dysplasia with prominent nuclear budding (Aspirate smears, Wright stain, 1000×); C. Focally increased eosinophils and precursors as well as erythroid dysplasia (Aspirate smears, Wright stain, 1000×); D. Hypercellular marrow with dysplastic megakaryocytes (Bone marrow core biopsy, H & E stain, 100×). [13-15]. The basophils in the peripheral blood limits. Basophilia can be seen rarely in acute and bone marrow are usually within normal myelogenous leukemia, typically with t(6;9) 5813 Int J Clin Exp Pathol 2015;8(5):5812-5820 Therapy-related AML with rearranged PDGFRA Figure 3. The absolute counts of peripheral blood with differential demonstrated marked leukocytosis with a rapid increase of eosinophils and basophils, along with circulating blasts. 5814 Int J Clin Exp Pathol 2015;8(5):5812-5820 Therapy-related AML with rearranged PDGFRA Figure 4. Acute myeloid leukemia with eosinophilia, basophilia and FIP1L1-PDGFRA. A. Eosinophila, basophilia and circulating blasts (Peripheral blood smear, Wright-giemsa stain, 1000×); B. Eosinophilia, basophilia and increased myeloblasts (Aspirate smears, Wright stain, 1000×); C. Hypercellular marrow with hypolobulated dysplastic mega- karyocytes (Bone marrow core biopsy, H & E stain, 100×); D. Markedly increased blasts (ALIP) as well as eosinophils and precursors (Bone marrow core biopsy, H & E stain, 200×); E. Approximately 20% CD34-positive blasts (Bone marrow core biopsy, immunostain, 100×); F. Normal number and morphology of tryptase-positive mast cells (Bone marrow core biopsy, immunostain, 100×). (p23;q34) (DEK-NUP214), which has distinct (q31;p13) has also been reported [17]. However, clinicopathological features of marrow basophi- the association of PDGFRA gene rearrange- lia, myelodysplasia and high prevalence of ment with basophilia has not been reported. FLT3-ITD mutations with poor prognosis [16]. A case of myelodysplastic syndrome accompa- Here, we report a unique case of therapy-rela- nied by basophilia and eosinophilia with t(5;12) ted acute myeloid leukemia after intensive che- 5815 Int J Clin Exp Pathol 2015;8(5):5812-5820 Therapy-related AML with rearranged PDGFRA Figure 5. Cytogenetic and FISH findings in acute myeloid leukemia with eosinophilia, basophilia and FIP1L1-PDGFRA. A. Complex karyotype with 45,XY,del(3)(p12), t(4;14)(q12;q24),der(5;21)(p10;q10),add(10)(q22). B and C. Com- plex karyotype with 50-51,XY,t(4;14)(q12;q24.3),+5,der(5;21)(p10;q10),+6,+8,+10,add(10)(q22)x2,+11,der(17) t(11;17)(q13;p11.2),+1-2mar. D. Interphase fluorescence in situ hybridization (FISH) tricolor 4q12 linked gene analysis: positive for loss of one FIP1L1 signal (green) and one CHIC2 signal (red) from the isolated PDGFRA signal (aqua). motherapy for prior B-ALL with eosinophilia, detected a population of blasts positive for TdT, basophilia, PDGFRA gene rearrangement, a CD34, CD45, CD19, CD20, CD22, and CD38, complex karyotype including t(4;14) and a very and negative for CD5, CD10, CD23 and CD117. poor clinical outcome. Cytogentic study showed a hypodiploid karyot- ype: 39,XY,-3,-7,-13,-14,-15,-16,-17[3]/78,ide- Case report mx2,-10,+13[9]/74,idemx2,t(2;5)(p21;p14), -4[3]/46,XY[5]. FISH was negative for BCR-ABL A 77-year-old male presented with weakness, gene fusion. He was diagnosed with B lympho- dyspnea on exertion, soaking sweats, low grade blastic leukemia (B-ALL) and treated with fever, loss of appetite, 20-30 pound weight Rituxan plus HyperCVAD (cyclophosphamide, loss, and lower gastrointestinal bleeding while on coumadin. A chest CT with contrast showed vincristine, doxorubicin, and dexamethasone; mediastinal lympoadenopathy (subcarinal ly- methotrexate and cytarabine) and POMP mph node measuring 3.5 × 2.3 cm and right (Purinethol, Oncovin, methotrexate, and predni- hilar lymph node measuring 2 × 2 cm). sone) plus Rituxan; and achieved completely Laboratory tests revealed a white blood cell remission. The subsequent restaging marrow count of 2.4 × 109/L, hemoglobin of 98 g/L, demonstrated no evidence of residual B-ALL by and platelets of 101 × 109/L. Chemistry profile IHC and flow cytometry. Cytogenetic study sho- and liver function tests were normal. Bone mar- wed normal male karyotype of 46, XY [20]. FISH row biopsy demonstrated hypercellular marrow study was negative for -7, and molecular stu- (95% cellularity) with 95% of blasts (Figure 1), dies were negative for clonal IgH and light chain which were positive for TdT, CD34, CD20 and gene arrangements. Thirteen months later, the negative for CD3, CD5, CD10, CD23, CD117, patient presented with mild anemia (hemoglo- MUM1, TRAP, Cyclin D1, and BCL6 by immu- bin: 10.7 g/dL), normal white blood cell and pla- nohistochemical stains (IHC). Flow cytometry telet counts. A restaging bone marrow biopsy 5816 Int J Clin Exp Pathol 2015;8(5):5812-5820 Therapy-related AML with rearranged PDGFRA showed no evidence of residual B-ALL, but mul- of the cells. Flow cytometry demonstrated tileage dysplasia and focally increased eosino- approximately 11% myeloblasts with aberrant phils (Figure 2). Cytogenetic study demonstra- expression of CD7 and no phenotypic evidence ted a complex karyotype of 45,XY,t(4;14)(q12; of B lymphoblastic leukemia. Given the intensi- q24),der(5;21)(p10;q10),add(10)(q22),der(17) ve chemotherapy received for B-ALL and com- t(11;17)(q13;p11.2)